1. Field of the Invention
The inventions disclosed herein relate in general to the field of medical connectors, and in particular to needle-less medical connectors.
2. Description of the Related Art
The manipulation of fluids for parenteral administration in hospitals and medical settings routinely involves the use of connectors for selectively facilitating the movement of fluids to or from patients. For example, a connector may be attached to a catheter that leads to a tip positioned within a patient, and various connectors may be attached to one or more tubes and medical implements to control the fluid flow to or from the patient.
Needle-less connectors are typically structured so that a medical implement without a needle can be selectively connected to such a connector for providing fluid flow between a patient and a fluid source or receptacle. When the medical implement is removed, the connector closes, effectively sealing the catheter connected to the patient without requiring multiple injections to the patient and without exposing health care professionals to the risk of inadvertent needle sticks. The medical implement used with the connector may be a tube or other medical device such as a conduit, syringe, IV set (both peripheral and central lines), piggyback line, or similar component which is adapted for connection to the medical valve.
Many existing medical connectors can be relatively difficult to grasp by health care professionals during use. In most applications, medical connectors are designed to be relatively small to minimize the cost of manufacturing and to minimize the amount of fluid “dead space” inside the connectors. Moreover, most medical connectors include a housing with a hard, smooth outer surface. As a result, it is sometimes uncomfortable for health care professionals to tightly pinch their fingers around the connectors and firmly grasp them during medical procedures in a repetitious manner. Because health care professionals use such connectors very frequently during patient care, enhancements in their ability to effectively grasp the connectors can result in significant improvement in the time and effort required to use them. Additionally, the existing hard-surface medical connectors can be uncomfortable against a patient's skin. This discomfort can become especially pronounced when a patient requires frequent medical attention involving the use of medical connectors, such as hemodialysis.
Additionally, many existing medical connectors at least partially obstruct fluid flow with complex flow passageways including various turns, bends, and corners. These obstructions can result in a fairly low flow rate. The obstructions can also damage blood platelets.
Further, many existing connectors permit some degree of retrograde fluid flow upon the disconnection of these medical devices from the valve. These connectors typically include an internal space through which a fluid may flow from the medical implement to the catheter attached to the connector. When the medical implement is attached to the connector, it typically occupies a portion of this internal valve space, displacing a certain amount of fluid within the connector. When the medical implement is disconnected, a vacuum is created by the removal of the portion of the medical implement from the internal space of the connector, which tends to draw fluid up through the line from the patient toward the connector to fill the space left by the removal of the implement.
This regression of fluid has certain disadvantages. When the connector is attached to a fluid line leading to a patient, retrograde movement of fluid through the line towards the space in the connector has the effect of drawing a small amount of blood away from the patient in the direction of the connector. The blood thus drawn into the catheter may, over time, result in a clog in the catheter near its tip, potentially limiting the effectiveness of the catheter tip.
The likelihood of blood clogging the tip of a catheter is heightened when the inner diameter of the catheter is small. In parenteral applications, such smaller-diameter catheters are used frequently due to their numerous advantages. For example, smaller catheters reduce the trauma and discomfort caused by insertion into a patient. Because these catheters have small lumens, even a small suction force may draw fluid back a comparatively large distance through the catheter toward the connector.
Further, in some existing medical connectors, there are gaps between an internal sealing member and the outer housing of the connector. These gaps may allow bacteria, debris, or disinfectant solution to enter through the opening into the interior of the connector and potentially reach the flow of fluid to or from the patient.